1/*
2 * Copyright (c) 2012-2015 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder. You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2006 The Regents of The University of Michigan
15 * Copyright (c) 2010 Advanced Micro Devices, Inc.
16 * All rights reserved.
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions are
20 * met: redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer;
22 * redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution;
25 * neither the name of the copyright holders nor the names of its
26 * contributors may be used to endorse or promote products derived from
27 * this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Authors: Ron Dreslinski
42 * Steve Reinhardt
43 * Ali Saidi
44 * Andreas Hansson
45 */
46
47/**
48 * @file
49 * Declaration of the Packet class.
50 */
51
52#ifndef __MEM_PACKET_HH__
53#define __MEM_PACKET_HH__
54
55#include <bitset>
56#include <cassert>
57#include <list>
58
59#include "base/cast.hh"
60#include "base/compiler.hh"
61#include "base/flags.hh"
62#include "base/misc.hh"
63#include "base/printable.hh"
64#include "base/types.hh"
65#include "mem/request.hh"
66#include "sim/core.hh"
67
68class Packet;
69typedef Packet *PacketPtr;
70typedef uint8_t* PacketDataPtr;
71typedef std::list<PacketPtr> PacketList;
72
73class MemCmd
74{
75 friend class Packet;
76
77 public:
78 /**
79 * List of all commands associated with a packet.
80 */
81 enum Command
82 {
83 InvalidCmd,
84 ReadReq,
85 ReadResp,
86 ReadRespWithInvalidate,
87 WriteReq,
88 WriteResp,
89 Writeback,
90 CleanEvict,
91 SoftPFReq,
92 HardPFReq,
93 SoftPFResp,
94 HardPFResp,
95 WriteLineReq,
96 UpgradeReq,
97 SCUpgradeReq, // Special "weak" upgrade for StoreCond
98 UpgradeResp,
99 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
100 UpgradeFailResp, // Valid for SCUpgradeReq only
101 ReadExReq,
102 ReadExResp,
103 ReadCleanReq,
104 ReadSharedReq,
105 LoadLockedReq,
106 StoreCondReq,
107 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
108 StoreCondResp,
109 SwapReq,
110 SwapResp,
111 MessageReq,
112 MessageResp,
113 // Error responses
114 // @TODO these should be classified as responses rather than
115 // requests; coding them as requests initially for backwards
116 // compatibility
117 InvalidDestError, // packet dest field invalid
118 BadAddressError, // memory address invalid
119 FunctionalReadError, // unable to fulfill functional read
120 FunctionalWriteError, // unable to fulfill functional write
121 // Fake simulator-only commands
122 PrintReq, // Print state matching address
123 FlushReq, //request for a cache flush
124 InvalidateReq, // request for address to be invalidated
125 InvalidateResp,
126 NUM_MEM_CMDS
127 };
128
129 private:
130 /**
131 * List of command attributes.
132 */
133 enum Attribute
134 {
135 IsRead, //!< Data flows from responder to requester
136 IsWrite, //!< Data flows from requester to responder
137 IsUpgrade,
138 IsInvalidate,
139 NeedsExclusive, //!< Requires exclusive copy to complete in-cache
140 IsRequest, //!< Issued by requester
141 IsResponse, //!< Issue by responder
142 NeedsResponse, //!< Requester needs response from target
143 IsSWPrefetch,
144 IsHWPrefetch,
145 IsLlsc, //!< Alpha/MIPS LL or SC access
146 HasData, //!< There is an associated payload
147 IsError, //!< Error response
148 IsPrint, //!< Print state matching address (for debugging)
149 IsFlush, //!< Flush the address from caches
150 NUM_COMMAND_ATTRIBUTES
151 };
152
153 /**
154 * Structure that defines attributes and other data associated
155 * with a Command.
156 */
157 struct CommandInfo
158 {
159 /// Set of attribute flags.
160 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
161 /// Corresponding response for requests; InvalidCmd if no
162 /// response is applicable.
163 const Command response;
164 /// String representation (for printing)
165 const std::string str;
166 };
167
168 /// Array to map Command enum to associated info.
169 static const CommandInfo commandInfo[];
170
171 private:
172
173 Command cmd;
174
175 bool
176 testCmdAttrib(MemCmd::Attribute attrib) const
177 {
178 return commandInfo[cmd].attributes[attrib] != 0;
179 }
180
181 public:
182
183 bool isRead() const { return testCmdAttrib(IsRead); }
184 bool isWrite() const { return testCmdAttrib(IsWrite); }
185 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
186 bool isRequest() const { return testCmdAttrib(IsRequest); }
187 bool isResponse() const { return testCmdAttrib(IsResponse); }
188 bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); }
189 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
190 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
191
192 /**
193 * Check if this particular packet type carries payload data. Note
194 * that this does not reflect if the data pointer of the packet is
195 * valid or not.
196 */
197 bool hasData() const { return testCmdAttrib(HasData); }
198 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
199 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
200 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
201 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
202 testCmdAttrib(IsHWPrefetch); }
203 bool isError() const { return testCmdAttrib(IsError); }
204 bool isPrint() const { return testCmdAttrib(IsPrint); }
205 bool isFlush() const { return testCmdAttrib(IsFlush); }
206
207 const Command
208 responseCommand() const
209 {
210 return commandInfo[cmd].response;
211 }
212
213 /// Return the string to a cmd given by idx.
214 const std::string &toString() const { return commandInfo[cmd].str; }
215 int toInt() const { return (int)cmd; }
216
217 MemCmd(Command _cmd) : cmd(_cmd) { }
218 MemCmd(int _cmd) : cmd((Command)_cmd) { }
219 MemCmd() : cmd(InvalidCmd) { }
220
221 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
222 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
223};
224
225/**
226 * A Packet is used to encapsulate a transfer between two objects in
227 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
228 * single Request travels all the way from the requester to the
229 * ultimate destination and back, possibly being conveyed by several
230 * different Packets along the way.)
231 */
232class Packet : public Printable
233{
234 public:
235 typedef uint32_t FlagsType;
236 typedef ::Flags<FlagsType> Flags;
237
238 private:
239
240 enum : FlagsType {
241 // Flags to transfer across when copying a packet
242 COPY_FLAGS = 0x0000000F,
243
244 SHARED = 0x00000001,
245 // Special control flags
246 /// Special timing-mode atomic snoop for multi-level coherence.
247 EXPRESS_SNOOP = 0x00000002,
248 /// Does supplier have exclusive copy?
249 /// Useful for multi-level coherence.
250 SUPPLY_EXCLUSIVE = 0x00000004,
251 // Snoop response flags
252 MEM_INHIBIT = 0x00000008,
253
254 /// Are the 'addr' and 'size' fields valid?
255 VALID_ADDR = 0x00000100,
256 VALID_SIZE = 0x00000200,
257
258 /// Is the data pointer set to a value that shouldn't be freed
259 /// when the packet is destroyed?
260 STATIC_DATA = 0x00001000,
261 /// The data pointer points to a value that should be freed when
262 /// the packet is destroyed. The pointer is assumed to be pointing
263 /// to an array, and delete [] is consequently called
264 DYNAMIC_DATA = 0x00002000,
265
266 /// suppress the error if this packet encounters a functional
267 /// access failure.
268 SUPPRESS_FUNC_ERROR = 0x00008000,
269
270 // Signal block present to squash prefetch and cache evict packets
271 // through express snoop flag
272 BLOCK_CACHED = 0x00010000
273 };
274
275 Flags flags;
276
277 public:
278 typedef MemCmd::Command Command;
279
280 /// The command field of the packet.
281 MemCmd cmd;
282
283 /// A pointer to the original request.
284 const RequestPtr req;
285
286 private:
287 /**
288 * A pointer to the data being transfered. It can be differnt
289 * sizes at each level of the heirarchy so it belongs in the
290 * packet, not request. This may or may not be populated when a
291 * responder recieves the packet. If not populated it memory should
292 * be allocated.
293 */
294 PacketDataPtr data;
295
296 /// The address of the request. This address could be virtual or
297 /// physical, depending on the system configuration.
298 Addr addr;
299
300 /// True if the request targets the secure memory space.
301 bool _isSecure;
302
303 /// The size of the request or transfer.
304 unsigned size;
305
306 /**
307 * Track the bytes found that satisfy a functional read.
308 */
309 std::vector<bool> bytesValid;
310
311 public:
312
313 /**
314 * The extra delay from seeing the packet until the header is
315 * transmitted. This delay is used to communicate the crossbar
316 * forwarding latency to the neighbouring object (e.g. a cache)
317 * that actually makes the packet wait. As the delay is relative,
318 * a 32-bit unsigned should be sufficient.
319 */
320 uint32_t headerDelay;
321
322 /**
323 * The extra pipelining delay from seeing the packet until the end of
324 * payload is transmitted by the component that provided it (if
325 * any). This includes the header delay. Similar to the header
326 * delay, this is used to make up for the fact that the
327 * crossbar does not make the packet wait. As the delay is
328 * relative, a 32-bit unsigned should be sufficient.
329 */
330 uint32_t payloadDelay;
331
332 /**
333 * A virtual base opaque structure used to hold state associated
334 * with the packet (e.g., an MSHR), specific to a MemObject that
335 * sees the packet. A pointer to this state is returned in the
336 * packet's response so that the MemObject in question can quickly
337 * look up the state needed to process it. A specific subclass
338 * would be derived from this to carry state specific to a
339 * particular sending device.
340 *
341 * As multiple MemObjects may add their SenderState throughout the
342 * memory system, the SenderStates create a stack, where a
343 * MemObject can add a new Senderstate, as long as the
344 * predecessing SenderState is restored when the response comes
345 * back. For this reason, the predecessor should always be
346 * populated with the current SenderState of a packet before
347 * modifying the senderState field in the request packet.
348 */
349 struct SenderState
350 {
351 SenderState* predecessor;
352 SenderState() : predecessor(NULL) {}
353 virtual ~SenderState() {}
354 };
355
356 /**
357 * Object used to maintain state of a PrintReq. The senderState
358 * field of a PrintReq should always be of this type.
359 */
360 class PrintReqState : public SenderState
361 {
362 private:
363 /**
364 * An entry in the label stack.
365 */
366 struct LabelStackEntry
367 {
368 const std::string label;
369 std::string *prefix;
370 bool labelPrinted;
371 LabelStackEntry(const std::string &_label, std::string *_prefix);
372 };
373
374 typedef std::list<LabelStackEntry> LabelStack;
375 LabelStack labelStack;
376
377 std::string *curPrefixPtr;
378
379 public:
380 std::ostream &os;
381 const int verbosity;
382
383 PrintReqState(std::ostream &os, int verbosity = 0);
384 ~PrintReqState();
385
386 /**
387 * Returns the current line prefix.
388 */
389 const std::string &curPrefix() { return *curPrefixPtr; }
390
391 /**
392 * Push a label onto the label stack, and prepend the given
393 * prefix string onto the current prefix. Labels will only be
394 * printed if an object within the label's scope is printed.
395 */
396 void pushLabel(const std::string &lbl,
397 const std::string &prefix = " ");
398
399 /**
400 * Pop a label off the label stack.
401 */
402 void popLabel();
403
404 /**
405 * Print all of the pending unprinted labels on the
406 * stack. Called by printObj(), so normally not called by
407 * users unless bypassing printObj().
408 */
409 void printLabels();
410
411 /**
412 * Print a Printable object to os, because it matched the
413 * address on a PrintReq.
414 */
415 void printObj(Printable *obj);
416 };
417
418 /**
419 * This packet's sender state. Devices should use dynamic_cast<>
420 * to cast to the state appropriate to the sender. The intent of
421 * this variable is to allow a device to attach extra information
422 * to a request. A response packet must return the sender state
423 * that was attached to the original request (even if a new packet
424 * is created).
425 */
426 SenderState *senderState;
427
428 /**
429 * Push a new sender state to the packet and make the current
430 * sender state the predecessor of the new one. This should be
431 * prefered over direct manipulation of the senderState member
432 * variable.
433 *
434 * @param sender_state SenderState to push at the top of the stack
435 */
436 void pushSenderState(SenderState *sender_state);
437
438 /**
439 * Pop the top of the state stack and return a pointer to it. This
440 * assumes the current sender state is not NULL. This should be
441 * preferred over direct manipulation of the senderState member
442 * variable.
443 *
444 * @return The current top of the stack
445 */
446 SenderState *popSenderState();
447
448 /**
449 * Go through the sender state stack and return the first instance
450 * that is of type T (as determined by a dynamic_cast). If there
451 * is no sender state of type T, NULL is returned.
452 *
453 * @return The topmost state of type T
454 */
455 template <typename T>
456 T * findNextSenderState() const
457 {
458 T *t = NULL;
459 SenderState* sender_state = senderState;
460 while (t == NULL && sender_state != NULL) {
461 t = dynamic_cast<T*>(sender_state);
462 sender_state = sender_state->predecessor;
463 }
464 return t;
465 }
466
467 /// Return the string name of the cmd field (for debugging and
468 /// tracing).
469 const std::string &cmdString() const { return cmd.toString(); }
470
471 /// Return the index of this command.
472 inline int cmdToIndex() const { return cmd.toInt(); }
473
474 bool isRead() const { return cmd.isRead(); }
475 bool isWrite() const { return cmd.isWrite(); }
476 bool isUpgrade() const { return cmd.isUpgrade(); }
477 bool isRequest() const { return cmd.isRequest(); }
478 bool isResponse() const { return cmd.isResponse(); }
479 bool needsExclusive() const { return cmd.needsExclusive(); }
480 bool needsResponse() const { return cmd.needsResponse(); }
481 bool isInvalidate() const { return cmd.isInvalidate(); }
482 bool hasData() const { return cmd.hasData(); }
483 bool isLLSC() const { return cmd.isLLSC(); }
484 bool isError() const { return cmd.isError(); }
485 bool isPrint() const { return cmd.isPrint(); }
486 bool isFlush() const { return cmd.isFlush(); }
487
488 // Snoop flags
489 void assertMemInhibit()
490 {
491 assert(isRequest());
492 assert(!flags.isSet(MEM_INHIBIT));
493 flags.set(MEM_INHIBIT);
494 }
495 bool memInhibitAsserted() const { return flags.isSet(MEM_INHIBIT); }
496 void assertShared() { flags.set(SHARED); }
497 bool sharedAsserted() const { return flags.isSet(SHARED); }
498
499 // Special control flags
500 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
501 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
502 void setSupplyExclusive() { flags.set(SUPPLY_EXCLUSIVE); }
503 bool isSupplyExclusive() const { return flags.isSet(SUPPLY_EXCLUSIVE); }
504 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
505 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
506 void setBlockCached() { flags.set(BLOCK_CACHED); }
507 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
508 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
509
510 // Network error conditions... encapsulate them as methods since
511 // their encoding keeps changing (from result field to command
512 // field, etc.)
513 void
514 setBadAddress()
515 {
516 assert(isResponse());
517 cmd = MemCmd::BadAddressError;
518 }
519
520 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
521
522 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
523 /**
524 * Update the address of this packet mid-transaction. This is used
525 * by the address mapper to change an already set address to a new
526 * one based on the system configuration. It is intended to remap
527 * an existing address, so it asserts that the current address is
528 * valid.
529 */
530 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
531
532 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
533
534 Addr getOffset(unsigned int blk_size) const
535 {
536 return getAddr() & Addr(blk_size - 1);
537 }
538
539 Addr getBlockAddr(unsigned int blk_size) const
540 {
541 return getAddr() & ~(Addr(blk_size - 1));
542 }
543
544 bool isSecure() const
545 {
546 assert(flags.isSet(VALID_ADDR));
547 return _isSecure;
548 }
549
550 /**
551 * It has been determined that the SC packet should successfully update
552 * memory. Therefore, convert this SC packet to a normal write.
553 */
554 void
555 convertScToWrite()
556 {
557 assert(isLLSC());
558 assert(isWrite());
559 cmd = MemCmd::WriteReq;
560 }
561
562 /**
563 * When ruby is in use, Ruby will monitor the cache line and the
564 * phys memory should treat LL ops as normal reads.
565 */
566 void
567 convertLlToRead()
568 {
569 assert(isLLSC());
570 assert(isRead());
571 cmd = MemCmd::ReadReq;
572 }
573
574 /**
575 * Constructor. Note that a Request object must be constructed
576 * first, but the Requests's physical address and size fields need
577 * not be valid. The command must be supplied.
578 */
579 Packet(const RequestPtr _req, MemCmd _cmd)
580 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false),
581 size(0), headerDelay(0), payloadDelay(0),
582 senderState(NULL)
583 {
584 if (req->hasPaddr()) {
585 addr = req->getPaddr();
586 flags.set(VALID_ADDR);
587 _isSecure = req->isSecure();
588 }
589 if (req->hasSize()) {
590 size = req->getSize();
591 flags.set(VALID_SIZE);
592 }
593 }
594
595 /**
596 * Alternate constructor if you are trying to create a packet with
597 * a request that is for a whole block, not the address from the
598 * req. this allows for overriding the size/addr of the req.
599 */
600 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize)
601 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false),
602 headerDelay(0), payloadDelay(0),
603 senderState(NULL)
604 {
605 if (req->hasPaddr()) {
606 addr = req->getPaddr() & ~(_blkSize - 1);
607 flags.set(VALID_ADDR);
608 _isSecure = req->isSecure();
609 }
610 size = _blkSize;
611 flags.set(VALID_SIZE);
612 }
613
614 /**
615 * Alternate constructor for copying a packet. Copy all fields
616 * *except* if the original packet's data was dynamic, don't copy
617 * that, as we can't guarantee that the new packet's lifetime is
618 * less than that of the original packet. In this case the new
619 * packet should allocate its own data.
620 */
621 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
622 : cmd(pkt->cmd), req(pkt->req),
623 data(nullptr),
624 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
625 bytesValid(pkt->bytesValid),
626 headerDelay(pkt->headerDelay),
627 payloadDelay(pkt->payloadDelay),
628 senderState(pkt->senderState)
629 {
630 if (!clear_flags)
631 flags.set(pkt->flags & COPY_FLAGS);
632
633 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
634
635 // should we allocate space for data, or not, the express
636 // snoops do not need to carry any data as they only serve to
637 // co-ordinate state changes
638 if (alloc_data) {
639 // even if asked to allocate data, if the original packet
640 // holds static data, then the sender will not be doing
641 // any memcpy on receiving the response, thus we simply
642 // carry the pointer forward
643 if (pkt->flags.isSet(STATIC_DATA)) {
644 data = pkt->data;
645 flags.set(STATIC_DATA);
646 } else {
647 allocate();
648 }
649 }
650 }
651
652 /**
653 * Generate the appropriate read MemCmd based on the Request flags.
654 */
655 static MemCmd
656 makeReadCmd(const RequestPtr req)
657 {
658 if (req->isLLSC())
659 return MemCmd::LoadLockedReq;
660 else if (req->isPrefetch())
661 return MemCmd::SoftPFReq;
662 else
663 return MemCmd::ReadReq;
664 }
665
666 /**
667 * Generate the appropriate write MemCmd based on the Request flags.
668 */
669 static MemCmd
670 makeWriteCmd(const RequestPtr req)
671 {
672 if (req->isLLSC())
673 return MemCmd::StoreCondReq;
674 else if (req->isSwap())
675 return MemCmd::SwapReq;
676 else
677 return MemCmd::WriteReq;
678 }
679
680 /**
681 * Constructor-like methods that return Packets based on Request objects.
682 * Fine-tune the MemCmd type if it's not a vanilla read or write.
683 */
684 static PacketPtr
685 createRead(const RequestPtr req)
686 {
687 return new Packet(req, makeReadCmd(req));
688 }
689
690 static PacketPtr
691 createWrite(const RequestPtr req)
692 {
693 return new Packet(req, makeWriteCmd(req));
694 }
695
696 /**
697 * clean up packet variables
698 */
699 ~Packet()
700 {
701 // Delete the request object if this is a request packet which
702 // does not need a response, because the requester will not get
703 // a chance. If the request packet needs a response then the
704 // request will be deleted on receipt of the response
705 // packet. We also make sure to never delete the request for
706 // express snoops, even for cases when responses are not
707 // needed (CleanEvict and Writeback), since the snoop packet
708 // re-uses the same request.
709 if (req && isRequest() && !needsResponse() &&
710 !isExpressSnoop()) {
711 delete req;
712 }
713 deleteData();
714 }
715
716 /**
717 * Take a request packet and modify it in place to be suitable for
718 * returning as a response to that request.
719 */
720 void
721 makeResponse()
722 {
723 assert(needsResponse());
724 assert(isRequest());
725 cmd = cmd.responseCommand();
726
727 // responses are never express, even if the snoop that
728 // triggered them was
729 flags.clear(EXPRESS_SNOOP);
730 }
731
732 void
733 makeAtomicResponse()
734 {
735 makeResponse();
736 }
737
738 void
739 makeTimingResponse()
740 {
741 makeResponse();
742 }
743
744 void
745 setFunctionalResponseStatus(bool success)
746 {
747 if (!success) {
748 if (isWrite()) {
749 cmd = MemCmd::FunctionalWriteError;
750 } else {
751 cmd = MemCmd::FunctionalReadError;
752 }
753 }
754 }
755
756 void
757 setSize(unsigned size)
758 {
759 assert(!flags.isSet(VALID_SIZE));
760
761 this->size = size;
762 flags.set(VALID_SIZE);
763 }
764
765
766 /**
767 * Set the data pointer to the following value that should not be
768 * freed. Static data allows us to do a single memcpy even if
769 * multiple packets are required to get from source to destination
770 * and back. In essence the pointer is set calling dataStatic on
771 * the original packet, and whenever this packet is copied and
772 * forwarded the same pointer is passed on. When a packet
773 * eventually reaches the destination holding the data, it is
774 * copied once into the location originally set. On the way back
775 * to the source, no copies are necessary.
776 */
777 template <typename T>
778 void
779 dataStatic(T *p)
780 {
781 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
782 data = (PacketDataPtr)p;
783 flags.set(STATIC_DATA);
784 }
785
786 /**
787 * Set the data pointer to the following value that should not be
788 * freed. This version of the function allows the pointer passed
789 * to us to be const. To avoid issues down the line we cast the
790 * constness away, the alternative would be to keep both a const
791 * and non-const data pointer and cleverly choose between
792 * them. Note that this is only allowed for static data.
793 */
794 template <typename T>
795 void
796 dataStaticConst(const T *p)
797 {
798 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
799 data = const_cast<PacketDataPtr>(p);
800 flags.set(STATIC_DATA);
801 }
802
803 /**
804 * Set the data pointer to a value that should have delete []
805 * called on it. Dynamic data is local to this packet, and as the
806 * packet travels from source to destination, forwarded packets
807 * will allocate their own data. When a packet reaches the final
808 * destination it will populate the dynamic data of that specific
809 * packet, and on the way back towards the source, memcpy will be
810 * invoked in every step where a new packet was created e.g. in
811 * the caches. Ultimately when the response reaches the source a
812 * final memcpy is needed to extract the data from the packet
813 * before it is deallocated.
814 */
815 template <typename T>
816 void
817 dataDynamic(T *p)
818 {
819 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
820 data = (PacketDataPtr)p;
821 flags.set(DYNAMIC_DATA);
822 }
823
824 /**
825 * get a pointer to the data ptr.
826 */
827 template <typename T>
828 T*
829 getPtr()
830 {
831 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
832 return (T*)data;
833 }
834
835 template <typename T>
836 const T*
837 getConstPtr() const
838 {
839 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
840 return (const T*)data;
841 }
842
843 /**
844 * return the value of what is pointed to in the packet.
845 */
846 template <typename T>
847 T get() const;
848
849 /**
850 * set the value in the data pointer to v.
851 */
852 template <typename T>
853 void set(T v);
854
855 /**
856 * Copy data into the packet from the provided pointer.
857 */
858 void
859 setData(const uint8_t *p)
860 {
861 // we should never be copying data onto itself, which means we
862 // must idenfity packets with static data, as they carry the
863 // same pointer from source to destination and back
864 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
865
866 if (p != getPtr<uint8_t>())
867 // for packet with allocated dynamic data, we copy data from
868 // one to the other, e.g. a forwarded response to a response
869 std::memcpy(getPtr<uint8_t>(), p, getSize());
870 }
871
872 /**
873 * Copy data into the packet from the provided block pointer,
874 * which is aligned to the given block size.
875 */
876 void
877 setDataFromBlock(const uint8_t *blk_data, int blkSize)
878 {
879 setData(blk_data + getOffset(blkSize));
880 }
881
882 /**
883 * Copy data from the packet to the provided block pointer, which
884 * is aligned to the given block size.
885 */
886 void
887 writeData(uint8_t *p) const
888 {
889 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
890 }
891
892 /**
893 * Copy data from the packet to the memory at the provided pointer.
894 */
895 void
896 writeDataToBlock(uint8_t *blk_data, int blkSize) const
897 {
898 writeData(blk_data + getOffset(blkSize));
899 }
900
901 /**
902 * delete the data pointed to in the data pointer. Ok to call to
903 * matter how data was allocted.
904 */
905 void
906 deleteData()
907 {
908 if (flags.isSet(DYNAMIC_DATA))
909 delete [] data;
910
911 flags.clear(STATIC_DATA|DYNAMIC_DATA);
912 data = NULL;
913 }
914
915 /** Allocate memory for the packet. */
916 void
917 allocate()
918 {
919 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
920 flags.set(DYNAMIC_DATA);
921 data = new uint8_t[getSize()];
922 }
923
924 /**
925 * Check a functional request against a memory value stored in
926 * another packet (i.e. an in-transit request or
927 * response). Returns true if the current packet is a read, and
928 * the other packet provides the data, which is then copied to the
929 * current packet. If the current packet is a write, and the other
930 * packet intersects this one, then we update the data
931 * accordingly.
932 */
933 bool
934 checkFunctional(PacketPtr other)
935 {
936 // all packets that are carrying a payload should have a valid
937 // data pointer
938 return checkFunctional(other, other->getAddr(), other->isSecure(),
939 other->getSize(),
940 other->hasData() ?
941 other->getPtr<uint8_t>() : NULL);
942 }
943
944 /**
945 * Is this request notification of a clean or dirty eviction from the cache.
946 **/
947 bool
948 evictingBlock() const
949 {
950 return (cmd == MemCmd::Writeback ||
951 cmd == MemCmd::CleanEvict);
952 }
953
954 /**
955 * Does the request need to check for cached copies of the same block
956 * in the memory hierarchy above.
957 **/
958 bool
959 mustCheckAbove() const
960 {
961 return (cmd == MemCmd::HardPFReq ||
962 evictingBlock());
963 }
964
965 /**
966 * Check a functional request against a memory value represented
967 * by a base/size pair and an associated data array. If the
968 * current packet is a read, it may be satisfied by the memory
969 * value. If the current packet is a write, it may update the
970 * memory value.
971 */
972 bool
973 checkFunctional(Printable *obj, Addr base, bool is_secure, int size,
974 uint8_t *_data);
975
976 /**
977 * Push label for PrintReq (safe to call unconditionally).
978 */
979 void
980 pushLabel(const std::string &lbl)
981 {
982 if (isPrint())
983 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
984 }
985
986 /**
987 * Pop label for PrintReq (safe to call unconditionally).
988 */
989 void
990 popLabel()
991 {
992 if (isPrint())
993 safe_cast<PrintReqState*>(senderState)->popLabel();
994 }
995
996 void print(std::ostream &o, int verbosity = 0,
997 const std::string &prefix = "") const;
998
999 /**
1000 * A no-args wrapper of print(std::ostream...)
1001 * meant to be invoked from DPRINTFs
1002 * avoiding string overheads in fast mode
1003 * @return string with the request's type and start<->end addresses
1004 */
1005 std::string print() const;
1006};
1007
1008#endif //__MEM_PACKET_HH